例7.12.frm

一本学习Visual Basic编程的好书

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   3195
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3195
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Sub Form_Load()
    Show
    Form1.BackColor = QBColor(15)   '设置背景颜色
    Call pict(30, 1600, 30)         '从小变大
    Call pict(1600, 30, -30)        '从大变小
End Sub
Private Sub pict(a, b, c)
    For i = a To b Step c
        Call plot(i, 4)            '显示圆
        delay 0.1                  '延迟0.1秒
        Call plot(i, 15)           '抹除
    Next i
End Sub
Private Sub delay(d)               '延迟过程
    T = Timer + d
    Do While Timer < T     '利用空循环实现延迟
    Loop
End Sub
Private Sub plot(r, clr)
    Form1.Circle (2400, 1600), r, QBColor(clr)     '画圆
End Sub